1. Field of the Invention
This invention relates generally to an apparatus for supporting the base of a ladder, and more particularly, to an apparatus for supporting the base of a ladder on a stairway such that the ladder may be rotated to any position where an upper portion of the ladder contacts the walls of the stairwell.
2. Description of the Related Art
In the past, various devices have been suggested in order to safely and conveniently use a ladder within a stairwell. These previous devices typically connect to the base of a ladder and provide adjustable length legs to correct for the uneven surface on which the ladder is to be placed. For example, U.S. Pat. No. 4,671,383 issued June 9, 1987 to Huang, illustrates a ladder leveller wherein the "downhill" leg of the ladder is adjustable to a length which compensates for the pitch of the stairway. The structure of Huang, however, prevents its use on opposite sidewalls without adjusting the leg lengths. Typically, a ladder is constructed with rungs having a flat step portion placed at an angle relative to the siderails of the ladder. Thus, a ladder is intended to be used from a single side and cannot simply be pivoted from one sidewall to the other. Rather, the relative leg lengths must be reversed when an operator desires to move from one sidewall to the other. Obviously, the leg lengths must be equalized when the operator desires to move to the stairwell endwall.
Alternatively, U.S. Pat. No. 4,457,397, issued July 3, 1984 to Schala, discloses a basic platform with adjustable legs that traverse multiple steps to provide a substantially planar base area on which to place the ladder. The platform disclosed in Schala is large and cumbersome, requiring six separate adjustments to properly position the platform within the stairwell. Aside from being difficult to position and adjust, Schala further suffers from the disadvantage of the ladder being unattached to the platform. Accordingly, a ladder placed on the Schala platform risks the possibility that the ladder base would slide rearwardly, causing an operator to fall. Schala has suggested the use of stepped portions on the platform surface which engage the base of the ladder and prevent undesirable movement of the base. However, these steps are necessarily positioned within the area in which an operator is expected to walk and, therefore, a risk exists that an operator will trip and fall. Further, reorienting the ladder to rest against the other sidewall or endwall requires the operator to support and balance the entire ladder. These ladders are typically large, heavy devices which prove difficult to maneuver, particularly within the close confines of a stairwell.
The present invention is directed to overcoming one or more of the problems as set forth above.